A set of Python utilities for rendering 3D meshes with OpenGL
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README.md

meshrender

A simple, OpenGL 3+ based Python scene renderer

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This package, which is build on top of PyOpenGL, is designed to make it easy to render images of 3D scenes in pure Python. It supports a scene abstraction and allows users to specify material properties, camera intrinsics, and lighting.

Extensive API documentation is provided here, but an example of using the library to render color and depth images is shown below.

    import numpy as np
    import trimesh
    from autolab_core import RigidTransform
    from perception import CameraIntrinsics, RenderMode

    from meshrender import Scene, MaterialProperties, AmbientLight, PointLight, SceneObject, VirtualCamera

    # Start with an empty scene
    scene = Scene()

    #====================================
    # Add objects to the scene
    #====================================

    # Begin by loading meshes
    cube_mesh = trimesh.load_mesh('cube.obj')
    sphere_mesh = trimesh.load_mesh('sphere.obj')

    # Set up each object's pose in the world
    cube_pose = RigidTransform(
        rotation=np.eye(3),
        translation=np.array([0.0, 0.0, 0.0]),
        from_frame='obj',
        to_frame='world'
    )
    sphere_pose = RigidTransform(
        rotation=np.eye(3),
        translation=np.array([1.0, 1.0, 0.0]),
        from_frame='obj',
        to_frame='world'
    )

    # Set up each object's material properties
    cube_material = MaterialProperties(
        color = np.array([0.1, 0.1, 0.5]),
        k_a = 0.3,
        k_d = 1.0,
        k_s = 1.0,
        alpha = 10.0,
        smooth=False
    )
    sphere_material = MaterialProperties(
        color = np.array([0.1, 0.1, 0.5]),
        k_a = 0.3,
        k_d = 1.0,
        k_s = 1.0,
        alpha = 10.0,
        smooth=True
    )

    # Create SceneObjects for each object
    cube_obj = SceneObject(cube_mesh, cube_pose, cube_material)
    sphere_obj = SceneObject(sphere_mesh, sphere_pose, sphere_material)

    # Add the SceneObjects to the scene
    scene.add_object('cube', cube_obj)
    scene.add_object('sphere', sphere_obj)

    #====================================
    # Add lighting to the scene
    #====================================

    # Create an ambient light
    ambient = AmbientLight(
        color=np.array([1.0, 1.0, 1.0]),
        strength=1.0
    )

    # Create a point light
    point = PointLight(
        location=np.array([1.0, 2.0, 3.0]),
        color=np.array([1.0, 1.0, 1.0]),
        strength=10.0
    )

    # Add the lights to the scene
    scene.ambient_light = ambient # only one ambient light per scene
    scene.add_light('point_light_one', point)

    #====================================
    # Add a camera to the scene
    #====================================

    # Set up camera intrinsics
    ci = CameraIntrinsics(
        frame = 'camera',
        fx = 525.0,
        fy = 525.0,
        cx = 319.5,
        cy = 239.5,
        skew=0.0,
        height=480,
        width=640
    )

    # Set up the camera pose (z axis faces away from scene, x to right, y up)
    cp = RigidTransform(
        rotation = np.array([
            [0.0, 0.0, -1.0],
            [0.0, 1.0,  0.0],
            [1.0, 0.0,  0.0]
        ]),
        translation = np.array([-0.3, 0.0, 0.0]),
        from_frame='camera',
        to_frame='world'
    )

    # Create a VirtualCamera
    camera = VirtualCamera(ci, cp)

    # Add the camera to the scene
    scene.camera = camera

    #====================================
    # Render images
    #====================================

    # Render raw numpy arrays containing color and depth
    color_image_raw, depth_image_raw = scene.render(render_color=True)

    # Alternatively, just render a depth image
    depth_image_raw = scene.render(render_color=False)

    # Alternatively, collect wrapped images
    wrapped_color, wrapped_depth, wrapped_segmask = scene.wrapped_render(
        [RenderMode.COLOR, RenderMode.DEPTH, RenderMode.SEGMASK]
    )